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61.
潘京全 《核电子学与探测技术》1991,(3)
本文介绍和评论了我所建立的环境实验室Ge(Li)γ谱仪系统的性能和应用。提出了一般环境实验室中使用一个中等体积和性能的高分辨率锗或Ge(Li)γ谱仪,加上适当的物质屏蔽就可以满足一般环境或生物样品中γ谱分析。 相似文献
62.
《Ergonomics》2012,55(2):151-162
The paper attempts to list the most important fields in which research on human factors in road transport is required. The importance of improving the efficiency of road transport is emphasized, and the figures for road casualties are quoted to demonstrate the need to study the behaviour of cyclists, motor-cyclists and pedestrians as well as motorists. The problems on which research is required are grouped under the six headings of perception, communication of information, control of the vehicle, comfort, protection of occupants, and behaviour of drivers. Subjects regarded as of particular interest are (1) the communication of information to the driver, (2) the design of the vehicle to improve control by the driver, (3) crash injury protection for the motorist and for the motor-cyclist, and (4) the study of the driving task. 相似文献
63.
The work presented in this paper focuses on improving coal loading performance of shear drum.Employing the similarity theory,we carried out a dimensional analysis of the correlation parameters which in... 相似文献
64.
A large number of high-voltage power transmission towers have recently been constructed in mining areas prone to subsidence.In order to ensure the safety of the transmission towers and the safe operati... 相似文献
65.
中央部门机关政府采购绩效评价,应该以党和国家关于缋效管理和政府采购的一系列重要文件为指导,针对政府采购工作全过程,以绩效目标为牵引,以绩效指标和评价标准为重点,以完善的评价组织方法为推动力,贴近实际、注重实效,按照事前、事中、事后三个阶段,客观评定中央部门机关政府采购工作投入产出比,以及工作的效益和效率情况,为政府采购工作的开展提供借鉴. 相似文献
66.
《Ergonomics》2012,55(11):1285-1297
Human factors and ergonomics research could benefit from focusing more strongly on individual differences – especially trait variables. The present study suggests the analysis of moderator effects as a promising way to enhance understanding of trait variables and process control performance. Process control performance was studied by analysing moderator effects of general mental ability (GMA) and need for cognition (NC) on risky decision-making (RDM) and performance. Fifty engineering students were trained on a process control task using a computer-based simulation for three hours and tested twice thereafter. Risky decision-making was measured using a computerised gambling task while GMA and NC were assessed with questionnaires. Risky decision-making in interaction with each GMA and NC explained variance in performance over and above variance explained by the single effects. In conclusion, the analysis of moderator effects between individual difference variables and process control performance seems promising. Practitioner Summary: Individual difference variables affect learning and performance, but have often not been studied to any great extent in human factors research. This article suggests a promising approach to studying individual differences – moderator analyses – and illustrates how such differences can lead to a better understanding of what determines process control performance. 相似文献
67.
For the blind recognition of Turbo codes in information interception, the recognition algorithm of turbo codes on trellis termination fall into following two parts. In coding structure recognition, turbo codes on trellis termination is defined as linear block codes, so the blind recognition of code length and start is achieved by analyzing the rank of codes matrix with a different number of columns and a different start; In encoder parameter recognition, by comparing the sequence matrix's column vector before and after interleaving and determining the decision threshold, the influence of error codes whose number is lower than the decision threshold is removed, and consequently, the problem of poor fault-tolerant performance in the traditional interleaving mode recognition method is solved. Simulation shows that the correct percentage of recognition is higher than 80% at 10-3 BER, and confirms the validity and reliability of the algorithm. 相似文献
68.
23 highly hypnotizable undergraduates (Harvard Group Scale of Hypnotic Susceptibility) underwent 2 specially constructed 7-item hypnotic inductions. Over the 14 items, the main finding was of a relationship between E. R. Hilgard's (1973, 1977, 1979) "hidden observer" effect and 2 aspects of hypnotic age regression. Ss reporting a hidden observer experienced duality during regression to age 5, in which they were aware of being both adult and child. When asked to write a complex sentence, most did so, usually without spelling errors. The Ss not reporting this effect experienced quasi-lateral age regression in which they had the exclusive feeling of being 5 yrs old, with no sense of an adult identity. Most of these Ss were unable to write the same complex sentence when requested to during age regression. The study replicated Hilgard's finding of the hidden observer phenomenon in terms of its incidence and obtained similar verbal reports from Ss experiencing it. At the same time, the results suggest that a neodissociation account of hypnosis may need some modifications to accommodate these additional findings. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
孔宪君 《黑龙江工程学院学报》2006,20(2):41-44
阐明多线程程序设计的概念和基本思想、线程的标准编程接口、多线程之间的互斥和同步、多线程中信号的处理等,通过网络发送和接收消息缓冲池队列管理的实例,给出多线程网络应用程序设计的方法. 相似文献
70.
可转债融资与公司股价长期表现实证研究 总被引:1,自引:0,他引:1
实证检验了我国上市公司可转债融资后的股价长期表现,结果发现,可转债融资后的公司股价并未如配股和增发再融资后的长期表现欠佳,而是有一定的优越表现.以EBIT与Size/BM可比公司进行调整后,一年期的累积超过收益分别为13.52%和17.13%,而以大盘指数调整后的一年期累积超额收益仅为0.41%.对以Size/BM可比公司调整后的累积超额收益给予的多元回归分析发现,可转债发行后的一年期股价市场表现与初始转换概率正相关,与股权稀释因子负相关,而在统计意义上不显著,但制造业公司在可转债发行后股价的一年期市场表现优于非制造业的公司,且在10%的水平下显著. 相似文献